Laser system and method for laser machining a workpiece

Abstract

A laser system for laser machining a workpiece using an interference pattern includes at least one laser beam source for providing a plurality of coherent laser beams, an amplification device for forming amplified coherent laser beams by amplifying the plurality of coherent laser beams, a phase adjustment device for adjusting a phase difference between the plurality of coherent laser beams and/or the amplified coherent laser beams, and a beam convergence region in which output laser beams based on the amplified coherent laser beams or corresponding to the amplified coherent laser beams converge to form the interference pattern. At least beam portions of the different output laser beams converge in the beam convergence region.

1 . A laser system for laser machining a workpiece using an interference pattern, the laser system comprising:
 at least one laser beam source for providing a plurality of coherent laser beams,   an amplification device for forming amplified coherent laser beams by amplifying the plurality of coherent laser beams,   a phase adjustment device for adjusting a phase difference between the plurality of coherent laser beams and/or the amplified coherent laser beams, and   a beam convergence region in which output laser beams based on the amplified coherent laser beams or corresponding to the amplified coherent laser beams converge to form the interference pattern, wherein at least beam portions of the different output laser beams converge in the beam convergence region.   
     
     
         2 . The laser system according to  claim 1 , wherein adjacent output laser beams present in the beam convergence region have at least beam portions which form an angle of at least 0.2° and/or at most 40°. 
     
     
         3 . The laser system according to  claim 1 , wherein, in the beam convergence region, adjacent output laser beams have beam portions which form a non-vanishing first angle associated with a first angular coordinate, wherein the first angle is at least 0.2° and/or at most 40°. 
     
     
         4 . The laser system according to  claim 3 , wherein, in the beam convergence region, adjacent output laser beams have beam portions which form a non-vanishing second angle associated with a second angular coordinate different from the first angular coordinate, wherein the second angle is at least 0.2° and/or at most 40°. 
     
     
         5 . The laser system according to  claim 4 , wherein adjacent output laser beams present in the beam convergence region are oriented with respect to one another in such a way that two adjacent output laser beams have either beam portions which form the non-vanishing first angle or beam portions which form the non-vanishing second angle. 
     
     
         6 . The laser system according to  claim 1 , wherein the output laser beams in the beam convergence region are present as collimated beam bundles, or the output laser beams in the beam convergence region are present as divergent beam bundles. 
     
     
         7 . The laser system according to  claim 1 , further comprising a focusing device for collimating and/or deflecting the amplified coherent laser beams incident on the focusing device. 
     
     
         8 . The laser system according to  claim 7 , wherein the focusing device comprises a focusing element, wherein the amplified coherent laser beams are incident on the focusing element, and wherein the amplified coherent laser beams are collimated and deflected by the focusing element in order to provide the output laser beams. 
     
     
         9 . The laser system according to  claim 7 , wherein the focusing device comprises a plurality of focusing elements, wherein each respective focusing element is associated with each respective amplified coherent laser beam, and wherein each respective amplified coherent laser beam is collimated by the respective focusing element. 
     
     
         10 . The laser system according to  claim 7 , wherein focusing elements of the focusing device and/or the amplified coherent laser beams incident on the focusing elements are configured and arranged such that laser beams emerging from the focusing elements form the beam convergence region and correspond to the output laser beams. 
     
     
         11 . The laser system according to  claim 1 , further comprising a beam deflection device for deflecting the amplified coherent laser beams in order to form the output laser beams converging in the beam convergence region. 
     
     
         12 . The laser system according to  claim 1 , wherein the amplified coherent laser beams coupled out of the amplification device are present as divergent beam bundles, wherein a main propagation direction of adjacent amplified coherent laser beams is oriented in parallel or transversely, and wherein the amplified coherent laser beams correspond to the output laser beams. 
     
     
         13 . The laser system according to  claim 1 , wherein the interference pattern has at least one interference element for laser machining of the workpiece, wherein the at least one interference element is repeated within the interference pattern. 
     
     
         14 . The laser system according to  claim 13 , wherein the interference element is repeated within the interference pattern at least 10 times. 
     
     
         15 . The laser system according to  claim 13 , wherein, by adjusting the phase difference between the coherent laser beams or the amplified coherent laser beams using the phase adjustment device, at least one property of the interference pattern and/or of the interference element is varied, wherein the at least one property comprises a distance between the interference elements, and/or a periodicity of the interference elements, and/or a peak intensity of the interference elements, and/or an intensity profile of the interference elements, and/or a geometric shape of the interference elements. 
     
     
         16 . The laser system according to  claim 1 , wherein the amplification device comprises a plurality of amplification elements, each respective amplification element for amplifying a respective coherent laser beam. 
     
     
         17 . A method for laser machining a workpiece using an interference pattern, the method comprising:
 providing a plurality of coherent laser beams by using at least one laser beam source,   amplifying the plurality of coherent laser beams to form amplified coherent laser beams by using an amplification device,   adjusting a phase difference between the plurality of coherent laser beams and/or the amplified coherent laser beams by using a phase adjustment device, and   forming output laser beams based on the amplified coherent laser beams or corresponding to the amplified coherent laser beams, wherein the output laser beams converge in a beam convergence region to form the interference pattern, and wherein at least beam portions of the different output laser beams converge in the beam convergence region.